Objective To investigate the prevalence of metabolically-healthy obese (MHO) and the incidence of diabetes after follow-up of 3 years in the Luzhou population of over the age of 40. Methods From April to August 2011, non-diabetes residents over the age of 40 were selected from three different street communities in Luzhou by multistage cluster sampling method. All the subjects accepted questionnaire investigation, physical examination and biochemical tests. Follow-up survey was carried out from June to October 2014. Results A total of 2442 subjects were included in our study (30.7% male). MHO accounted for 14.8%, the incidence of male MHO was 11.2% and that of female MHO was 15.4%; metabolically-healthy non-obese (MHNO) accounted for 45.3%, metabolically-
unhealthy obese (MUHO) for 19.5% and metabolically-unhealthy non-obese (MUHNO) for 20.4%. Over the median follow-up of 3 years, 248 cases had type 2 diabetes. Compared with MHNO individuals, MHO subjects had 1.64 times risk of diabetes(95% CI: 0.99-2.70), MHO women had 2.05 times risk (95% CI, 1.15-3.65), MUHO cases had 5.23 times risk (95% CI, 3.72-7.36), MUHNO cases had 3.93 times risk (95% CI: 2.74-5.64). After the follow-up of three years, the abnormal index percentages of the MHO group included triglyceride (TG) 34.3%, systolic blood pressure (SBP) 39.4%, diastolic blood pressure (DBP) 22.6%, fasting blood sugar (FBS) 8.3%, OGTT 2-h glucose 43.4%, which significantly increased compared with those of the MHNO group (P < 0.05). Conclusions The prevalence of MHO among women and relatively-young people is higher. Diabetes incidence of MHO subjects is obviously lower than that of MUHO and MUHNO individuals, diabetes incidence of MHO women is higher than that of MHNO ones. Metabolic abnormalities occur more often in MHO individuals than in MHNO people.